#ifndef _MEMDC_H_
#define _MEMDC_H_


class CMemDC : public CDC
{
private:	
	CBitmap m_bitmap;		
	CBitmap* m_oldBitmap;
	CDC* m_pDC;	
	CRect m_rect;
	BOOL m_bMemDC;
public:

	CMemDC(CDC* pDC, const CRect* pRect = NULL) : CDC()
	{
		ASSERT(pDC != NULL); 

		m_pDC = pDC;
		m_oldBitmap = NULL;
		m_bMemDC = !pDC->IsPrinting();

		if (pRect == NULL)
		{
			pDC->GetClipBox(&m_rect);
		}
		else
		{
			m_rect = *pRect;
		}

		if (m_bMemDC)
		{
			CreateCompatibleDC(pDC);
			pDC->LPtoDP(&m_rect);

			m_bitmap.CreateCompatibleBitmap(pDC, m_rect.Width(),
						m_rect.Height());
			m_oldBitmap = SelectObject(&m_bitmap);

			SetMapMode(pDC->GetMapMode());

			SetWindowExt(pDC->GetWindowExt());
			SetViewportExt(pDC->GetViewportExt());

			pDC->DPtoLP(&m_rect);
			SetWindowOrg(m_rect.left, m_rect.top);
		}
		else
		{
			m_bPrinting = pDC->m_bPrinting;
			m_hDC = pDC->m_hDC;
			m_hAttribDC = pDC->m_hAttribDC;
		}

		FillSolidRect(m_rect, pDC->GetBkColor());
	}

	~CMemDC()
	{
		if (m_bMemDC)
		{
			m_pDC->BitBlt(m_rect.left, m_rect.top, m_rect.Width(),
					m_rect.Height(), this, m_rect.left, m_rect.top, SRCCOPY);			

			SelectObject(m_oldBitmap);
		}
		else
		{
			m_hDC = m_hAttribDC = NULL;
		}
	}

	CMemDC* operator->()
	{
		return this;
	}	

	operator CMemDC*()
	{
		return this;
	}
};

#endif